simplefb: add support for a8b8g8r8 pixel format

A framebuffer of this format is set up by SHIELD's bootloader.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

Documentation/devicetree/bindings/video/simple-framebuffer.txt

@@ -12,6 +12,7 @@ Required properties:
 - stride: The number of bytes in each line of the framebuffer.
 - format: The format of the framebuffer surface. Valid values are:
   - r5g6b5 (16-bit pixels, d[15:11]=r, d[10:5]=g, d[4:0]=b).
+  - a8b8g8r8 (32-bit pixels, d[31:24]=a, d[23:16]=b, d[15:8]=g, d[7:0]=r).
 
 Example:
 

drivers/video/simplefb.c

@@ -84,6 +84,7 @@ struct simplefb_format {
 
 static struct simplefb_format simplefb_formats[] = {
 	{ "r5g6b5", 16, {11, 5}, {5, 6}, {0, 5}, {0, 0} },
+	{ "a8b8g8r8", 32, {0, 8}, {8, 8}, {16, 8}, {24, 8} },
 };
 
 struct simplefb_params {